Conventional cordlock structures often include a locking means comprising a locking dog assembly made up of a long first arm pivotally connected to the cap portion and a short arm pivotally connected to the long arm. Each arm has a locking portion on the distal end thereof adapted to lockingly engage with blind operating cords passing therebetween and the pivot axes of the two arms are positioned inside of the path of the operating cords through the cap portion with respect to the blind assembly. In some cordlock structures having this type of locking means, it is necessary in order to lower the blind assembly to pull the operating cords slightly in a vertical direction beneath the locking means, and then release the cords under the control of the operator until the blind is lowered the desired amount after which the operator stops the cords with his hand and pulls the cords away from the blind assembly in order to lock the locking means.
In order to raise the blind assembly with this type of locking means, the cords are pulled either downwardly or to one side or outwardly of the blind assembly and then locked in the same manner as in lowering the blind assembly. A problem with this structure however is that if the operator accidentally releases an operating cord, except at the designated locking position where the cord is pulled away from the plane of the blind assembly, the blind assembly supported by the cord will fall to a tilted or fully down position.
Cordlock structures having the locking means as described above could be made to automatically lock when the operating cord drops or falls to a vertical position and be unlocked by moving the cords in a direction towards the plane of the blind assembly. This would require that the cap portion containing the locking means be positioned sufficiently away from the plane of the blind assembly so that there is room to move the operating cord towards the blind assembly without interferring with the blind assembly. This positioning of the cap portion a sufficient distance away from the plane of the blind assembly would result in the cordlock structure being larger than is aesthetically desirable.
In some instances it is desirable that the cords operate in planes substantially parallel to the plane of the blind assembly and be pulled in a direction towards the center of the blind assembly during raising or lowering. This occurs particularly when drapes may be positioned at ends of the blind assembly which would then interfere with cords being moved towards and away from the plane of the blind assembly. Conventional cordlock structures may be modified to allow movement of the cords in a plane parallel to the plane of the blind assembly by turning the structure 90.degree. towards the blind but then the structure is incapable of being used where it may still be desirable to also have an operating mode in which the cords can be moved towards or away from the plane of the blind assembly. Further if the operator were to accidently release the cords using such conventional cordlock structure, they would fall to a vertical position allowing the blind assembly to fall to a tilted or fully lowered position as previously explained.
Cordlock structures are conventionally made of plastic moldings and because of expense and color retention characteristics, plastics are often used which do not have good wear resistant properties. Modern blind assemblies have small diameter operating cords to improve the appearance of the blind assembly, and where the blind assembly is of substantial weight, these small diameter cords may wear and gouge into the plastic material comprising the cordlock assembly. Because of expense of material, and difficulty in coloring and color retention of some plastic materials, it often is not feasible to make the cordlock structure of highly wear resistant structure.
The headrails and slats of blind assemblies often come in a variety of colors, and for aesthetic reasons, it is desirable that the colors making up the various parts of the blind assembly, including cordlock structures, be the same or coordinated with each other. This however may present a problem, as in the case of cordlock structures, if inventories of many different colored structures must be maintained.
It is therefore an object of my invention to provide for a cordlock structure which will have a locking means which will automatically move to a locked position when operating cords beneath the locking means are moved or allowed to move to a vertical position and which may be moved to an unlocked position by moving the cords away from the plane of the blind assembly.
It is still a further object of my invention to provide for a cordlock structure which will be unobtrusive and which at the same time may be operated by moving blind operating cords in a plane parallel to the blind assembly or by moving the cords away from the blind assembly and which will have a locking means which will move automatically to a locked position when the cords are moved to or allowed to fall to a vertical position.
It is also an object of the invention to provide for a cordlock structure which includes a cover which may cover the external surfaces of the locking structure and where the cover is of a color to coordinate with the color of a headrail.
It is a further object of my invention to provide for a cordlock structure which may comprise an inexpensive plastic material having desired color and color retention properties and which at the same time will have wear resistant surfaces to prevent wear or gouging by blind operating cords.